Conventionally, component mounting devices are known in which an adhesive sheet for fixing a mounted component is attached to a display panel such as a liquid crystal panel, and the mounted component is pressed onto the adhesive sheet. For example, there are electronic component mounting devices in which, after attaching ACF (anisotropic conductive film) with attached release sheet to a liquid crystal panel, and then peeling off the ACF's release sheet, a TCP (thin LSI-chip package) is pressed onto the ACF, and the TCP is mounted onto the liquid crystal panel.
FIG. 12 shows process drawings of a conventional ACF attaching device. A head 101 is arranged facing a stage 100. The head 101 is provided with a pressure applying surface 101a. A reel 104 is arranged on the supply side of an ACF 102. The ACF 102 with attached release sheet is wound around the reel 104. The ACF 102 is supplied onto the stage 100 via supply rollers 105a to 105d. 
FIG. 12A shows the initial state of an ACF attaching operation. The leading edge of the ACF 102 is positioned at a cutter 108. In the step of FIG. 12B, a predetermined length of the ACF 102 is drawn out onto the stage 100 by a feed chuck 107. The drawing out of the film is performed by the feed chuck 107 moving in the direction of arrow a with a chuck portion of the feed chuck 107 clamping the release sheet 103.
As can be seen in FIG. 12B, with the ACF 102 drawn out by a predetermined length required for a single attachment (hereafter, “single attachment unit”), the ACF 102 is cut by the cutter 108, leaving the release sheet 103 intact. After cutting, the cutter 108 withdraws from above the stage 100. In this condition, a substrate is supplied onto the stage.
FIG. 12C shows a single attachment unit of the ACF 102 being pressed onto a substrate 110 by the head 101. Here, the pressure applying surface 101a is heated to a predetermined temperature, and presses the substrate 110 with the ACF 102 inbetween. The ACF 102 is attached to the substrate 110, and the head 101 moves up.
After this, while a sheet lock 109 clamps and holds the release sheet 103, and while the feed chuck 107 is open, the feed chuck 107 is moved toward the supply side of the ACF 102, and peeled off from the ACF 102 that is attached to the substrate 110. After this peeling off, successive single attachment units of ACF 102 are attached to the remaining attachment locations on the substrate 110 by repeating the steps shown in FIGS. 12B and 12C. When all ACF attachments for the substrate 110 are complete, the substrate 110 is transported to the next process.
Here, ACF 102 is wound onto the reel 104, but in order to supply as much ACF as possible with a single reel, sometimes a reel is used wound with ACF that is made of multiple continuous connected ACFs. When such a reel is used, a joint is formed at the connecting portion between the ACFs, but because the length of ACF wound around the single reel becomes longer, the number of reel replacements can be reduced.
Furthermore, whether using a reel on which multiple continuous ACFs are not connected, or whether using a reel on which multiple continuous ACFs are connected by a joint, in either case an end mark is formed on the end position of the ACF on the single reel, and it can be confirmed that the ACF on the reel has run out when this end mark appears.
However, conventional ACF attaching devices such as those described above have the following problems. When using a reel wound with joined ACF, a portion containing a joint cannot be used for attachment to a substrate. For this reason, when a joint appears, it is necessary to stop production temporarily, and peel off the portion containing a joint.
If production is set up for the joint to appear when production is finished, reductions in the operation ratio can be suppressed by using the periods in which the equipment is not operative, peeling off the portion containing a joint, and setting the equipment to an initial state as in FIG. 12A. However, the time when the joint appears varies depending on the length of attachments, and the type of reel, and in most cases it is impossible to ensure that the joint appears at the end of production. For this reason, it is necessary to stop the ACF attaching device temporarily during production when a joint appears.
In this case, the ACF containing a joint is peeled off from the release sheet, and in many cases an attachment length longer than a single attachment unit remains in this peeled off portion, so that there are many cases of wastefully peeling off more film than necessary and not making use of and attaching to a substrate the usable limit of ACF up to the joint. Thus there is the problem of resource loss.
Furthermore, there is also the problem that, after the joint appears, the successive operation of peeling off the joined portion of ACF is a manual task, and therefore takes time in preparation.
Furthermore, when the ACF is provided with an end mark, the usable limit of ACF up to the end mark is not made use of and attached to a substrate when the end mark is recognized. Thus there is the problem of wasting resources.